If I was to say that I have a dog at my house. People having dogs in thier house is a common occurance, so most people would accept it, but clearly you would not. You would demand proof.
If there was a dusty old book from 2,000 years ago that claimed that there was a purple pony that the equivelant of a John Smith rode into town one day, would you believe it? Considering that you believe something even more outlandish, I'm guessing you would.
I think you have your priorieties backwards.